How many significant figures does $00.78972000$ have?
Explanation: Identify the non-zero digits and any zeros between them. These are all significant. $00.{78972}000$ Leading zeros are not significant. $\color{orange}{00.}{78972}000$ Since there is a decimal, trailing zeros are significant. $\color{orange}{00.}{78972000}$ Counting all the significant digits gives us 8.